1. Field of the Invention
Aspects of the present invention relate to a tag authentication method using rotation, and a tag and reader performing the method.
2. Description of the Related Art
A personal area network (PAN) refers to a communication network to process necessary information using a portable information terminal. The PAN is smaller than a local area network (LAN), and includes a system which transmit/receives various information using a personal information terminal or a system which uses saltwater of a human body as a conductor to exchange information easily. In the system using saltwater as a conductor, an electric signal of a card computer is transmitted to another card computer by shaking hands. For another example, the PAN can be configured using a radio frequency identification (RFID) system.
The RFID system wirelessly receives/transmits various kinds of data using a particular frequency band. A magnetic strip, a barcode, and the like are easily damaged by wear and a recognition performance thereof gradually deteriorates. However, an RFID system can overcome the above-described disadvantages in the magnetic strip, the barcode, and the like. Accordingly, the RFID system is replacing barcode and magnetic cards in the marketplace, and is the fastest growing segment in security services, time cards, parking management, and goods distribution management fields.
FIG. 1 illustrates an example of a typical RFID system. The RFID system described above generally includes a tag 101, a reader 102, and a back-end database 103. In this instance, a communication environment between the reader 102 and the back-end database 103 can be a secure channel 104, and a communication environment between the reader 102 and the tag 101 can be an insecure channel 105.
As described above, since an insecure channel 105 is used between the reader 102 and the tag 101 in the RFID system, a reliable tag authentication method and a system which can prevent tag spoofing and securely authenticate the tag are needed.